How To Fix CN645 - The assignment exists already

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 645

• Message text: The assignment exists already

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message CN645 - The assignment exists already ?

  The SAP error message CN645 ("The assignment exists already") typically occurs in the context of project management or cost center assignments within the SAP system. This error indicates that there is an attempt to create an assignment (such as a cost element, project, or activity) that already exists in the system.
  Cause:
  
  Duplicate Assignment: The most common cause is that the assignment you are trying to create already exists in the system. This could be due to a previous entry that was not properly deleted or an attempt to reassign an existing object.
  Incorrect Data Entry: Sometimes, the error can arise from incorrect data entry, where the system interprets the input as a duplicate.
  Configuration Issues: There may be configuration settings that prevent the creation of multiple assignments for the same object.
  
  Solution:
  
  Check Existing Assignments: Before creating a new assignment, check the existing assignments for the object in question. You can do this by navigating to the relevant transaction (e.g., CN41 for project structures) and reviewing the current assignments.
  Modify Existing Assignment: If the assignment already exists and you need to make changes, consider modifying the existing assignment instead of creating a new one.
  Delete Duplicate Assignments: If you find that there are indeed duplicates that should not exist, you may need to delete the unnecessary assignments. Ensure you have the necessary authorizations to perform this action.
  Consult Documentation: Review the SAP documentation or help files related to the specific module you are working with (e.g., Project System, Controlling) for more detailed guidance on handling assignments.
  Contact Support: If you are unable to resolve the issue, consider reaching out to your SAP support team or consulting with an SAP expert who can provide assistance based on your specific configuration and setup.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CN41 (Project Structure), CJ20N (Project Builder), or CJI3 (Project Actual Line Items) to help you navigate and troubleshoot.
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP Notes can provide insights into specific bugs or configuration settings that may be causing the issue.
  User Authorizations: Ensure that you have the appropriate authorizations to create or modify assignments in the system, as lack of permissions can sometimes lead to unexpected errors.
  
  By following these steps, you should be able to identify the cause of the CN645 error and take appropriate action to resolve it.